Door closer



P H. SHACKLETON ET AL 2,328,851

DOOR CLOSER Filed June 5, 1942 110 u an tors .ZfSkacileta-zv 1). .Po clb uzv X ms with, a roller on a vertica1axiswhich engages in Q a'channel elementletinto the .frame' of the door.

differential band brake, while in the' opening a V assisted by the light p'ress'ureof the leaf spring' 24. {3

Theizbrakamay be constantly applied throughout,

7 one the drum =it maybe secured-to the brake {band i m medeo con az ,l m leia pm-proj n m'flhgnl mRefer I y L V spring -2 operating to hold thebra-h band on I The main arm H1 at its free end is provided As an alternative a channel member may'be provided with lugs for securing it upon the surface of the frame or other suitablemeans, such as are used in existing doorfclosers, may be employed; for connecting the main arm to thedoor.

aid

7 7 It is to be noted that ftheidifierntial' brallee' means are so arranged tha'fidurlngitheclosing" movement of the door the brake is automatically put on in accordance with thaknow'noperation of movement the brake doeslnot operate and while this is the preferredarrangement, the brake may "15 he designed to:operatei-wjthaan initial-load on the regulating 'armtasmy :al si litabiei spring otherithan eTheapplicati'on of-theVbrakeWill'be-airtomatically themlosing movement ori-regulated at anyzpoint intsjby the'iactionaand'contonr ofthe cam.

Thus; if thezcam- 2 iiistprovided with a single rise ith wbrakei mayeb'e effective-1until-rshortly before therdooncloseswvhen the-brakeis releasedtol allow the mink-pressure .of theimain spring S -to givea Y slight' slam to operate the latch. -01; the. other hanmxii thecamrhayseveral rises; the brake will haveza numben' of ofiw-and ,on m ovements.

lineman thefmo-ller; =23 'on lthe -regulating arm 2 lifanr adjustable screvw maybe-provided or the arm maybear directlyonthecam; z .cThe brakes ba'nd' I'll may ialsq-eomprise a strip instead'of a'continuonsrbandfihe:ends being'suitably secured to the eccentrically rmountedanchor adsseae neegas m gma meat s as indicated in Figure 3,

vMe t ha l e ing 'the'bra eadi ust'i a spindle =1 r y'c be r q e to l Eig p i a; iinsteadisiqf .the leaf .215

. the drum; a dual pn rpese: springmzi rmayt be provided." This I spring; 52.5 as secured :tq. -t-he brake band anchor -l d -and- F etweenz twoacljustableisorewstops-*2 e' stop zfi serves towkeepwband Han won act witha'the drum 42'. The stop-21 1is; for ithelpurposeyot :oontrolling the maximum am m i f braking enorta neremaite explained. 4 .7

It iswell kno -tha t inbarid brakesi fthe type a pulling mnf wilh lessen them-brakingaefiect. This ipivotandlanchor-be back pressure isobtained by the engagement of the spring 25 with stop 21 which is adjusted so:

that the pulling on oi the brake is lessened at its maximum. This has the 'efiect of speeding up the first part oi-the closing of the'door.

The dual purpose spring may be used in conjunction with the cam-2|. It will be appreciated that owing to the dinerential action'of the brake resultin in a strong action'during closingof the door and a relatively weak action during opening of the door, it may Tin ome; circumstances be unnecessary to provide jiithe cambr'ake release means According to a modification the drum may be fixed'toj the case and thebrake band with the:

arranged tUIOtat ."a'Weiclaim: L a '3 1; Ardoorl'closer having check means including ia' difierential bandlbrakev comprising. atdrumziand 1 a band encircling theqdrum and connected todifierential levels, 1 arranged? so i that the braking efiectris, greateruin thelcl'osing movement :thanin the opening movement ofv-rthezdoor; and; resilient l -rneans :operatively. connected toethe; difierential ileveis adapted normally-to hold; thewbrakezband' on then-rumtto provide a prelo adingf-rof the brake.

#2.. Aqcloorcl'oser as claimed in:-'claim hwherein therres'ilientz means araarranged-so :that. :the; self induced resistance-of therbrake automatically .re-'

Lduc eS on-temporarily :removes the prelieading. v 1 '3; wA' doorrcloser as claimed in-tclaim-lg wherein the resilient means comprises'ia spring operatively connected :to the difierentialglevers and operating lagainst an- -adjustable istop whereby the self .in-,

duped resistances-of -.the: brake automatically -reduces or temporarily removes the preloading;

-"Q'SfA doonelos'er having; checlgmeans including a differentialband: brakecomprisinga drum and a band encircling the drum and connected-todifl ferential--levers larrangedg so rthatlthefbraking; ef- 1 feet-is; greater in the elesingrmovementthanin l the .ppening rnovement oi the. door, .and .;resilient means ioperativelyl connected to the; differential levers adapted normally Tte holdthe brake on the 1 drum to provide a: preloading. ofv-lthe brake-and tesue r m ee P P i m ;ih le ke a forleontrolling themaxirnum brake pressure.

I fafn door. -cl0seriasiClailnedlin claim 4,- wherein theresilient meanscom ialspring operatively connected, toi 'th. differentlalalevers and. mier at- I 'ing betweenadjustable straps,

A door close]; havinglchecklmeansincluding v a difiierential bandit-ea egeempnsm a drum and ahand encircling the drumgthe ends bf the band securedto pivoted anchor-means forming thee-diff jerentialj -leve'rs of thebrake Q-aleaflspringsecured L to said anchor and having airee end located between adjustable z'stops; said free end normally 5 'securedsto the casing, a spring c ap' to-which the employedhereinithe-heavierthe load tobe braked, OthQIqEIliOf =the spring is secured-said vcasing the harder-thebrakegis -pulledon-land the-anchor enclosing the differential band brake, said ,capv '18 is'pulled {further over iopyaaheavyl loadtthan being-secured tozthe drum ofsaidbrake, said anwithcadight one. .EEhus thessuperimposition of a choribeing pivotallyniounted on-thecasing. back-pressure on heancl orin ,opposition-tothe {l0 HARRYv-SHACKLETON.

' 1; JALFRED gpAvls Pool-1m; 

